The Oklahoma City Thunder were already facing a tough task in the Western Conference Finals against the San Antonio Spurs, before they lost Serge Ibaka for the remainder of the playoffs. The Spurs have one of the top offenses in the league, with the ball flowing through multiple hands on every possession and rim pressure almost a certainty every time down the floor.

Ibaka, quite simply, was a security blanket. With athletes such as Russell Westbrook, ThaboSefolosha, Reggie Jackson and Kevin Durant on the perimeter, the Thunder's most effective defense involved gambling for steals, playing passing lanes and double-teaming. If they were burned, Ibaka was there to clean up the mess.

Through two games of this series, we've seen the Thunder play their usual, undisciplined defense. The only difference has been a lack of protection inside, and the gambles that are normally bailed out by Ibaka are costing the team buckets. Without a more conservative style of defense, Oklahoma City could find itself going home quickly.

Take this play from early in the first quarter of Game 2, when the Spurs ran a simple "zipper" cut to get Tony Parker the ball at the top of the key. This initial cut is part of a sequenced play and only intended to get the ball inbounds. What develops afterwards is the true play, in which the Spurs try to get a basket.

The zipper cut starts with Parker at the block and Tim Duncan setting a screen to free him up. Parker cuts off the screen towards the ball, with all his momentum headed away from the basket. Yet Sefolosha, who is guarding Parker, tries to follow Parker a bit too closely by mimicking his direct path. This "lock and trail" is completely unnecessary because Sefolosha should know Parker is not looking to score immediately. The only reason to do this, then, is to gamble for a steal.

Unfortunately for Sefolosha, he gets a bit hung up in the Duncan screen. Instead of aborting the lock and trail, going underneath the screen and getting back into a guarding position, he tries to fight through. This puts him in a compromised position, however, when Parker makes the catch. Notice the angle he's now taken:

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All Parker has to do is spin around and head towards the basket. The rest of the OKC defense is not expecting this wide open lane and cannot react quick enough. Parker gets an easy layup slicing down the middle.

With Ibaka on the team, it's likely that this mess would have been cleaned up. Parker, like most players. typically has a tough time finishing over Ibaka and would have been forced to pass the ball out. This would have given the Thunder extra time to recover and realign their defense.

What makes the Spurs so dangerous on the offensive end isn't necessarily their one-on-one ability; it's that all five players understand how to pass the ball to undermine pressure. We've seen OKC trap, double-team and throw other weird coverages at San Antonio to slow down their offense; schemes which have largely failed. This is because San Antonio rarely makes the home run pass, instead choosing to swing the ball quickly until someone comes open.

Looking at the Spurs' roster on an individual level, only Parker is good enough to consistently take advantage of his matchup. He's arguably the quickest point guard in the league and certainly the NBA's most clever finisher. Otherwise, San Antonio has simply sprinkled its roster with players who pass and fit a role.

Where OKC is finding trouble is in their over-compensation toward the ball. Though Parker is a dangerous player, he's not always in a dangerous position. Duncan, as effective as he is this late in his career, is no longer a guaranteed two points on the block. Kawhi Leonard, for all his athleticism and shooting, still cannot create that well in isolation. Manu Ginobili, for all his herky-jerky stylings that lead to seemingly impossible baskets, cannot blow by his man without a little pick-and-roll help.

What every player does do is recognize the right initial pass on every play. Where San Antonio thrives is in beating a base defense before it's fully rotated into its assignments. The Spurs eschew primary action for secondary and tertiary play.

OKC wants to blow up a pick-and-roll with pressure? A San Antonio ball-handler will recognize it before the defender can pounce. Two or three ball swings later and the defense is in utter chaos. They ping the ball around until a defender over/under/improperly rotates, and capitalize on these far easier advantages. Instead of trying to create something out of nothing, the Spurs move the ball until the defense screws up.

That's what happens here in transition, when Parker pushes the ball and throws it to Danny Green in the corner. As one of the best shooters in the league, Green has the green light to let it fly whenever he's open. OKC's Jackson realizes this and quickly scrambles to contest a potential shot as soon as he sees the pass coming.

Though his effort is excellent, the angle he takes is poor. Because he moves at Green on a path directly in line with him, it gives Green the option of driving either way. He obviously doesn't want to get stuck in the corner, so he goes left and towards the middle of the floor.

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Using Duncan's screen, Green is now out of trouble and free to operate. But there's a secondary consequence to Jackson's closeout as well: Green is such a dangerous shooter that Jackson is up in his space, meaning Duncan can easily get a piece of Jackson. This forces a switch between Durant and Jackson, and Durant is now guarding Green.

This might seem like a mismatch, but this is where San Antonio's patience comes into play. The true mismatch is Jackson on Duncan. Instead of trying to attack a player who customarily doesn't guard him, Green swings it to Splitter at the top of the key. All Tiago has to do now is throw an easy and high pass to Duncan, who finishes for two points. The 10-inch difference in height means Jackson has no chance.

There's nothing spectacular about these offensive possessions other than San Antonio pouncing on OKC's mistakes. It's nearly impossible to play perfect defense on a given possession, and there is almost always a mismatch to exploit. The Spurs are so calculating and consistent at finding these advantages that it makes their offensive basketball look mind-bogglingly easy.

Let's be clear, though: It's not that easy. Very few players have the will power to make the right decision on every play, let alone most players on an entire team. It's a testament to Gregg Popovich and his staff that the Spurs play this way, and it's beautiful to watch.

Moving forward, OKC needs to do a better job of picking its poison. Instead of going for steals, over-switching and playing any other type of gambling defense, they need to make San Antonio beat them man-to-man. Live with a Parker mid-range jumper. Live with a contested three-pointer by Leonard. Live with Splitter going one-on-one in the post.

Protect the paint, don't go for turnovers and be boring on defense. That's the only way they'll have a chance in this series. Otherwise, the Spurs will continue to slice and dice OKC's defense en route to any shot they want.